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Mechanical power generation using Earth's ambient radiation

science.org

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Re: Mechanical power generation using Earth's ambient radiation

#11

Post by andbberger »

jasonpeacock wrote: post #5
HPsquared wrote: post #2

Somewhat different, but this reminds me of an approach that uses temperature gradients in the ocean to power a heat engine. https://en.wikipedia.org/wiki/Ocean_thermal_energy_conversio...

OTECs are amazing, and step 1 of "The Millennial Project: Colonizing the galaxy in eight easy steps"[0] [0]: https://en.wikipedia.org/wiki/The_Millennial_Project There's a shore-based research OTEC in Hawaii, but the best is a floating, closed-loop OTEC in the ocean.

wiki article states "Up to 10,000 TWh/yr of power could be generated from OTEC without affecting the ocean's thermal structure". which converts to about 500GW which... isn't that much

Re: Mechanical power generation using Earth's ambient radiation

#13

Post by ufocia »

AnimalMuppet wrote: post #9
aetherspawn wrote: post #4

Earlier quoted context omitted.

> the generation of >400 milliwatts per square meter of mechanical power with a potential for >6 watts per square meter. Keep in mind the power is fully mechanical so no electricity or control circuit is required. And based on the simplicity it seems like a good candidate to power something that you need to last 100 years with no maintenance for example.

Mechanical things don't usually work for 100 years with no maintenance. Bearings run dry, if nothing else.

Air bearings always run dry without problems.

Re: Mechanical power generation using Earth's ambient radiation

#14

Post by jcims »

DIY radiative cooling paint from YouTuber NightHawkInLight - https://www.youtube.com/watch?v=N3bJnKmeNJY&list=PL1a2HkcVbm...

It has pretty impressive performance.

Tech Ingredients did one or two vids as well - https://www.youtube.com/watch?v=dNs_kNilSjk

Was thinking of whipping up a batch for my rv.

Re: Mechanical power generation using Earth's ambient radiation

#15

Post by pezezin »

andbberger wrote: post #11
jasonpeacock wrote: post #5

Earlier quoted context omitted.

OTECs are amazing, and step 1 of "The Millennial Project: Colonizing the galaxy in eight easy steps"[0] [0]: https://en.wikipedia.org/wiki/The_Millennial_Project There's a shore-based research OTEC in Hawaii, but the best is a floating, closed-loop OTEC in the ocean.

wiki article states "Up to 10,000 TWh/yr of power could be generated from OTEC without affecting the ocean's thermal structure". which converts to about 500GW which... isn't that much

10 000 TWh/yr is one third of the current total electric energy generation of the whole planet, is not a small amount.

Source, page 39 of the full report:

https://www.iea.org/reports/global-energy-review-2025/electr...

Re: Mechanical power generation using Earth's ambient radiation

#17

Post by kogasa240p »

Since we're talking about stirling engines, I've always wondered how using geothermal heat for a larger stirling engine would work.

https://youtu.be/duuk_r--lqU?t=99

Even though the video uses the sun to heat the oil, I would think it would be feasible to use geothermal heat instead.

Re: Mechanical power generation using Earth's ambient radiation

#18

Post by contingencies »

ufocia wrote: post #13
AnimalMuppet wrote: post #9

Earlier quoted context omitted.

Mechanical things don't usually work for 100 years with no maintenance. Bearings run dry, if nothing else.

Air bearings always run dry without problems.

Until they are replaced with dust, pollution, hair, animals, leaf litter, aggressive plants, seismic events, pollen, skin particles, birdshit, fallen logs, slime mold, etc.

Re: Mechanical power generation using Earth's ambient radiation

#19

Post by 15155 »

AnimalMuppet wrote: post #3

400 milliwatts per square meter? That's interesting that they can do it at all, but that level is completely impractical for real use.

This is plenty of power to run a microcontroller and a radio (sporadically) with an energy-harvesting setup.

Re: Mechanical power generation using Earth's ambient radiation

#20

Post by nrhrjrjrjtntbt »

foxglacier wrote: post #7
AnimalMuppet wrote: post #3

400 milliwatts per square meter? That's interesting that they can do it at all, but that level is completely impractical for real use.

So what? It's research, not business. Surely you didn't expect they'd found a practical source of free energy that was ready to compete with solar but somehow nobody else bothered to try before?

It is interesting to know if it has potential (pun intended) for some use. Even if that is some very niche thing.
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